Head-mounted display, head-mounted display linking system, and method for same

ABSTRACT

A head-mounted display comprises: a wearing body; a display; a communication module configured to perform communication connection with a mobile information terminal; a field of view (FOV) sensor configured to output status data used for determining whether the mobile information terminal is included in a user&#39;s FOV through the wearing body; and a controller connected to each of the display, the communication module, and the FOV detection sensor. The controller determines whether the mobile information terminal is included in the user&#39;s FOV based on the status data, and performs display control with respect to the display so as to display an application screen of the mobile information terminal on the display when determining that the mobile information terminal is not included in the FOV, and not to display the application screen on the display when determining that the mobile information terminal is included in the FOV.

TECHNICAL FIELD

The present invention relates to a display technique of a head-mounteddisplay (hereinafter abbreviated as “HMD”).

BACKGROUND ART

As background art to which the present invention belongs, PatentLiterature 1 discloses a system which is configured to “calculatepositional information of head-mounted display wearer's gaze withrespect to primary information based on a camera image acquired from thehead-mounted display and a position of the head-mounted display wearer'sgaze with respect to the camera image, select and display secondaryinformation associated with the calculated positional information, andchange how the secondary information is displayed depending on whetherthe wearer is looking at the primary information” (excerpted fromAbstract).

Patent Literature 2 discloses “a head-mounted display device whichallows a user to view a virtual image and an outside scene, comprising:a generation unit configured to generate an image list including a firstimage which is a display image of an external device connected to thehead-mounted display device and a second image which is possessed by thehead-mounted display device; and an image display unit configured toform a virtual image representing the generated image list” (excerptedfrom Abstract).

CITATION LIST Patent Literature

-   Patent Literature 1: WO-A-2017/104089-   Patent Literature 2: JP-A-2015-222891

SUMMARY OF INVENTION Technical Problem

The systems disclosed in Patent Literature 1 and Patent Literature 2 areconfigured to allow a display image to be shared with the HMD when theHMD and the external display device are connected to communicate to eachother. Accordingly, when the prior art above is applied to a mobileinformation terminal and the HMD which have a communication function,the display image of the mobile information terminal is displayed on theHMD upon link establishment between the HMD and the mobile informationterminal. With this configuration, even in a case where displaying of animage is not expected nor demanded by a user, a screen of the mobileinformation terminal may be displayed, resulting in inconvenience inuse.

The present invention has been made in view of the circumstances above,and an object of the present invention is to provide a linkage techniquebetween an HMD and a mobile information terminal, which is configured todisplay a screen of the mobile information terminal on the HMD at atiming useful for a user, thereby realizing good operability.

Solution to Problem

In order to solve the problems above, the present invention includes thetechnical features described in the scope of claims. As an examplethereof, the present invention provides a head-mounted displaycomprising: a wearing body to be worn on a head of a user; a displayprovided on the wearing body in front of the user's eyes; acommunication module configured to perform communication connection witha mobile information terminal; a field of view detection sensorconfigured to output status data used for determining whether the mobileinformation terminal is included in a field of view of the user throughthe wearing body; and a controller connected to each of the display, thecommunication module, and the field of view detection sensor, whereinthe controller is configured to: determine whether the mobileinformation terminal is included in the field of view of the user basedon the status data; and perform display control with respect to thedisplay so as to display an application screen, which displays anexecution state of application program for realizing a specific functionexecuted by the mobile information terminal, on the display whendetermining that the mobile information terminal is not included in thefield of view, and not to display the application screen on the displaywhen determining that the mobile information terminal is included in thefield of view.

Advantageous Effects of Invention

According to the present invention, it is possible to provide a linkagetechnique between an HMD and a mobile information terminal, which isconfigured to display a screen of the mobile information terminal on theHMD at a timing useful for a user, thereby realizing good operability.The problems, configurations, and effects other than those describedabove will be clarified by explanation of the embodiments below.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a schematic diagram of an HMD linking system.

FIG. 2 is a hardware block diagram of an HMD.

FIG. 3 is a software block diagram of an HMD.

FIG. 4 is a hardware block diagram of a mobile information terminal.

FIG. 5 is a software block diagram of a mobile information terminal.

FIG. 6 illustrates an example of a sequence of an HMD linking systemaccording to a first embodiment.

FIG. 7 illustrates a flowchart showing a flow of application screendisplay control processing according to the first embodiment.

FIG. 8 illustrates a positional relationship between a field of view anda mobile information terminal (application screen is not displayed).

FIG. 9 illustrates a scene which is obtained through a display when anapplication screen is not displayed.

FIG. 10 illustrates a positional relationship between a field of viewand a mobile information terminal (application screen is displayed).

FIG. 11 illustrates a scene which is obtained through a display when theapplication screen is displayed.

FIG. 12 illustrates a variation of an application screen display startcondition according to a second embodiment.

FIG. 13 illustrates a re-display position after framing out.

FIG. 14 illustrates an example of a sequence of an HMD linking systemaccording to a fourth embodiment.

FIG. 15 illustrates screen transition of an HMD.

DESCRIPTION OF EMBODIMENTS

Hereinafter, embodiments of the present invention will be described withreference to the drawings. Throughout the drawings, the same componentsare provided with the same reference signs and repetitive explanationthereof will be omitted.

First Embodiment

The first embodiment is an embodiment in which when an HMD and asmartphone as a mobile information terminal is connected to communicateto each other and when the mobile information terminal is not in a fieldof view of a user wearing the HMD, an application screen of the mobileinformation terminal is displayed on the HMD. The term “applicationscreen” mentioned herein means a screen on which an execution status ofan application program executed on the mobile information terminal isdisplayed.

FIG. 1 is a schematic diagram of an HMD linking system 100. The HMDlinking system 100 is configured by an HMD 10 and a mobile informationterminal 80 which are wirelessly connected to perform communicationtherebetween. FIG. 1 illustrates a smart phone as the mobile informationterminal 80, meanwhile, any types of the mobile information terminal 80may be used as long as it is a mobile image display device such as atablet terminal or a smart watch.

The HMD 10 mainly includes a wearing body 1, a display 2, an outsidecamera 3, an inside camera 4, and an HMD controller 5.

The wearing body 1 is a member that maintains a state where the HMD 10is mounted on the head of a user M of the HMD 10 (see FIG. 8 and FIG. 10) and holds other components of the HMD 10. FIG. 1 illustrates thewearing body 1 in the shape of glasses, meanwhile, the shape is notlimited thereto.

The display 2 is a transmissive liquid crystal display and is arrangedon the wearing body 1 in front of the eye of the user M.

The outside camera 3 is a camera equipped with a CCD or a CMOS, whichis, when it is defined that a side of the wearing body 1 facing the faceof the user M is an inside while a side opposite to the inside is anoutside, provided on a front outside of the wearing body 1. The outsidecamera 3 is provided on the wearing body 1 at a position and orientationincluding a field of view of the user M within an angle of view.

The inside camera 4 is a camera equipped with a CCD or a CMOS, which isprovided on the inside of the wearing body 1 at a position andorientation on which movement of the eye of the user M can be imaged.

The HMD controller 5 is configured by using a processor or a circuit forperforming communication control of the mobile information terminal 80and display control of the display 2. In the present embodiment, anexample in which a general purpose computer is used to execute softwarefor realizing functions of an HMD linking method according to thepresent embodiment will be described.

FIG. 2 is a hardware block diagram of the HMD 10.

As illustrated in FIG. 2 , the HMD 10 includes the HMD controller 5, animaging unit 120, an audio unit 130, an operation unit 140, acommunication module 150, a sensor unit 160, an extension I/F 170, and adisplay unit 180 which are connected to each other by a system bus 102.

The HMD controller 5 includes a CPU (Central Processor) 101, a ROM (ReadOnly Memory) 103, a RAM (Random Access Memory) 104, an HDD (Hard DiskDrive), and a storage 110 which comprises an SSD (Solid State Drive)having a semiconductor memory such as a flash memory.

The imaging unit 120 includes the outside camera 3, the inside camera 4,and an image signal processor 121 configured to convert output signalsof each camera into image signals.

The audio unit 130 includes a microphone 131 configured to input sound,an audio signal processor 132 including noise processing andamplification processing of an audio signal from the microphone 131, anda speaker 133 configured to reproduce a ring tone and sound.

The operation unit 140 includes an operation button and an operationswitch, which are configured by an operation member such as an ON/OFFbutton of a main power supply of the HMD 10 or a volume dial thereof.Each operation member has a function as an operation detection sensorsince they are members for detecting that an input operation has beenmade by accepting an operation of the user.

The communication module 150 includes a wireless LAN communicationdevice (transmitter and receiver) 151 for connecting the HMD 10 to awireless LAM such as Wi-Fi (registered trademark), Infraredcommunication, or the like, and a near filed wireless device(transmitter and receiver) 152 using Bluetooth (registered trademark) orthe like.

The sensor unit 160 includes a GPS (Global Positioning System) 161, agyro sensor 162 configured to detect changes in rotation and direction,a geomagnetic sensor 163 configured to measure orientation, anacceleration sensor 164 configured to detect data relating toinclination, movement, vibration, and impact, an illuminance sensor 165configured to detect brightness of the surrounding of the HMD 10, aproximity sensor 166, a distance sensor 167, and a line of sightdetection sensor 168. The gyro sensor 162, the acceleration sensor 164,the line of sight detection sensor 168 are used as a field of viewdetection sensor for detecting a field of view of the user M in eachembodiment.

The display unit 180 includes the display 2 and a display controller 182configured to perform generation and output control of data to bedisplayed on the display 2.

FIG. 3 is a software block diagram of the HMD 10.

The ROM 103 includes a basic operation program 103 a and other programs103 b of the HMD 10. The basic operation program 103 a includes anactivation program of the HMD 10, a display control program of a topscreen (see a top screen 1501 of FIG. 15 ) to be displayed during normalactivation processing, and a program for communicating with the mobileinformation terminal 80.

The RAM 104 is an area where the CPU 101 loads the programs stored inthe ROM 103 or the storage 110 during execution thereof. Duringexecution of each program, a basic operation execution unit 104 a, aninformation display execution unit 104 b, and a temporary storage area104 c are generated in the RAM 104. The information display executionunit 104 b includes a screen transfer middleware 104 b 1 configured todisplay or not display an application screen of the mobile informationterminal 80 on the HMD 10, and an operation execution unit 104 b 2.

The screen transfer middleware 104 b 1 is a program for performingdisplay and control of the application screen on the display 2 of theHMD 10. In the present embodiment, the screen transfer middleware 104 b1 is configured as middleware, meanwhile, the function thereof may berealized by a daemon or a driver which is operated on the OS.Furthermore, instead of the screen transfer middleware 104 b 1, anapplication that individually corresponds to each application of themobile information terminal 80 and is operated on the HMD 10 may beemployed.

The storage 110 stores a various information data storage area 110 a, aninformation display program 110 b, and other programs 110 c. A screenmovement flag (see FIG. 7 ), which will be described later, may beprovided in the various information data storage area 110 a or in thetemporary storage area 104 c of the RAM 104. In addition, small regionmanagement data for dividing the display 2 into a plurality of smallregions and managing them, which will be described later, is also storedin the various information data storage areas 2.

FIG. 4 is a hardware block diagram of the mobile information terminal80. The components common to the hardware configuration of the HMD 10are provided with the same names as those of the HMD 10, and illustratedwith reference signs 201 to 282. The hardware configuration of themobile information terminal 80 differs from the hardware configurationof the HMD 10 in that the line of sight detection sensor 168 provided inthe HMD 10 is not provided, and that a terminal communication module 250includes a telephone network communication device (transmitter andreceiver) 253 for connecting the mobile information terminal 80 to 3G or4G network. Here, an inside camera 224 of the mobile informationterminal 80 is a camera which is provided on a surface of the mobileinformation terminal 80 on which a terminal display 281 is provided(front surface), which allows to perform so-called self-photographing.An outside camera 223 is a camera which is provided on a back surface.

FIG. 5 is a software block diagram of the mobile information terminal80. The components common to the software configuration of the HMD 10are provided with the same names as those of the HMD 10, and illustratedwith reference signs 201 to 210 c. The software configuration of themobile information terminal 80 differs from the software configurationof the HMD 10 in that the screen transfer middleware 104 b 1 is notprovided, and that a transfer corresponding application program 204 dfor linking the mobile information terminal 80 with the HMD 10 todisplay an application screen on the HMD 10, is provided. The transfercorresponding application program 204 d is one of the applicationprogram installed respectively in the mobile information terminal 80,which has a function of displaying an application screen on the HMD 10.The function of the transfer corresponding application program, such asa map navigation application program, an electronic book applicationprogram, etc., is not limited. In the present embodiment, an example inwhich the transfer corresponding application program 204 d is used willbe described. Meanwhile, it may be configured to execute a screentransfer middleware on the mobile information terminal 80 to display ascreen, which is displayed on the terminal display 281 of the mobileinformation terminal 80, on the HMD 10, without making each applicationcorrespond to screen transfer.

In addition, the transfer corresponding application program 204 d may beconfigured to display the screen in high resolution or low resolution inaccordance with display capability of the mobile information terminal 80and the HMD 10 and/or using scenes thereof, and moreover, may beconfigured to perform detailed display or simplified display.

The HMD 10 and the mobile information terminal 80 may be connected bynear field wireless communication or a wireless LAN. They may alsocommunicate by Peer-to-Peer and one-to-one, or via a cloud.

As a mode of transferring the application screen from the mobileinformation terminal 80 to the HMD 10, the application screen displayedon the terminal display 281 of the mobile information terminal 80 may becaptured and then transferred. In such a case, a still image istransferred. Upon capturing a screen, the screen may be updatedperiodically. In addition, both the mobile information terminal 80 andthe HMD 10 may store the transfer corresponding application program 204d, respectively, so that the transfer corresponding application program204 d stored in the HMD 10 and the transfer corresponding applicationprogram 204 d stored in the mobile information terminal 80 aresynchronized to display the screen having the same content as the screenof the terminal display 281 on the display 2 of the HMD 10, instead oftransferring screen data by linking the operations of each of thetransfer corresponding application program 204 d. Furthermore, a motionimage may be transferred from the transfer corresponding applicationprogram 204 d to the HMD 10 by means of streaming or the like.

With reference to FIGS. 6 to 11 , an outline of processing of the HMDlinking system 100 will be described. FIG. 6 illustrates a flowchartshowing a flow of the processing of the HMD linking system 100. FIG. 7illustrates a flowchart showing a flow of application screen displaycontrol processing according to the first embodiment. FIG. 8 illustratesa positional relationship between the field of view and the mobileinformation terminal 80 (application screen is not displayed). FIG. 9illustrates a scene which is obtained through the display 2 when theapplication screen is not displayed. FIG. 10 illustrates a positionalrelationship between the field of view and the mobile informationterminal 80 (application screen is displayed). FIG. 11 illustrates ascene which is obtained through the display 2 when the applicationscreen is displayed. Hereinafter, the processing will be described inaccordance with an order of steps illustrated in FIG. 6 .

Both the mobile information terminal 80 and the HMD 10 are activated(step S01, step S02). Either of the HMD 10 and the mobile informationterminal 80 may be activated first, or both the HMD 10 and the mobileinformation terminal 80 may be activated at the same time. In FIG. 6 ,the mobile information terminal 80 is activated first.

The mobile information terminal 80 makes a connection request to the HMD10 (step S03) to establish a link (step S04).

After the link is established, the transfer corresponding applicationprogram 204 d of the mobile information terminal 80, which isapplication program stored in the mobile information terminal 80, isactivated (step S05). The transfer corresponding application program 204d transmits an application activation notification, which indicates thatthe transfer corresponding application program 204 d has been activated,to the HMD 10 (step S06).

The HMD controller 5 receives the application activation notification,and then activates the screen transfer middleware 104 b 1 stored in theHMD 10 (step S07).

The screen transfer middleware 104 b 1 makes the outside camera 3 of theHMD 10 start capturing, and then the outside camera 3 starts outputtingan image to the HMD controller 5 (step S08). Since the outside camera 3includes the field of view of the user of the HMD 10 within its angle ofview, an imaging area of the outside camera 3 herein is assumed to bethe same as the field of view of the user M on the HMD 10.

The HMD controller 5 executes processing to display the applicationscreen on the display 2 (application screen display control processing)(step S09). In the first embodiment, whether the mobile informationterminal 80 is present in the image taken by the outside camera 3 isused as a start condition (trigger) for displaying the applicationscreen.

As illustrated in FIG. 7 , a screen transfer middleware 104 b 1 acquiresan image taken by the outside camera 3 (step S091), and executes imagerecognition processing for recognizing whether a subject (object) in theimage is the mobile information terminal 80 (step S092). There areseveral specific algorithms of the image recognition processing. Forexample, a front surface of the mobile information terminal 80 is imagedin advance by the outside camera 3, and a front image obtained by theimaging above is held as teacher data. Then, subject extractionprocessing is performed on the image taken by the outside camera 3, andpattern matching processing between the subject and the teacher data isexecuted. When the degree of matching is equal to or greater than apredetermined threshold value, the mobile information terminal 80 may bedetermined to be the subject. In a case of using the front image, theprocessing may be configured not to recognize that the subject is themobile information terminal 80 when the mobile information terminal 80in the image taken by the outside camera 3 is turned upside down, liedon its side, or partially shielded by being placed behind something.

When it is determined that the subject is the mobile informationterminal 80 (step S093/Yes), in other words, when it is determined thatthe mobile information terminal 80 is in the field of view asillustrated in FIG. 8 , the HMD controller 5 sets a value of a screentransfer flag to “0” (step S094), and does not display the applicationscreen on the display 2. In the case above, as illustrated in FIG. 9 ,the user M can visually recognize the mobile information terminal 80through the display 2 of the HMD. In this way, the user M does notvisually recognize the application screen on the display 2 but directlywatches the application screen displayed on the terminal display 281through the display 2.

When it is determined that the subject is not the mobile informationterminal 80 (step S093/No), in other words, when it is determined thatthe mobile information terminal 80 is not in the field of view asillustrated in FIG. 10 , the HMD controller 5 sets the value of thescreen transfer flag to “1” (step S095), and displays the applicationscreen on the display 2. In the case above, as illustrated in FIG. 11 ,the user M visually recognizes the application screen displayed on thedisplay 2.

While the application screen is displayed on the display 2 of the HMD10, the application screen of the terminal display 281 of the mobileinformation terminal 80 may be hidden or continuously displayed.Processing in which the mobile information terminal 80 displays or hidesthe application screen, or performs transition from a display operationto a sleep operation (operation of hiding and darkening the screen) maybe executed by a screen control function of the mobile informationterminal 80, or the transfer corresponding application program 204 d mayhave the screen control function.

When a termination condition of the application display screen controlprocessing is satisfied (step S096/Yes), the screen transfer middleware104 b 1 terminates the application screen control processing. When thetermination condition of the application screen control processing isnot satisfied (step S096/No), the screen transfer middleware 104 b 1returns to step S091 and repeatedly acquires images from the outsidecamera 3. As a result, unless the termination condition is satisfiedduring link establishment, the user M wearing the HMD 10 and watchingthe mobile information terminal 80 visually recognizes the actualapplication screen of the mobile information terminal 80, while, whenthe user M removes the mobile information terminal 80 from the field ofview, for example, lowers the hand holding the mobile informationterminal 80 or puts the mobile information terminal 80 into a pocket ora bag, the application screen is displayed on the HMD 10.

When the termination condition of the application screen controlprocessing is satisfied, the link between the HMD 10 and the mobileinformation terminal 80 may be released, or the link may be maintainedwhile terminating only the screen transfer middleware 104 b 1. In such acase, when the activation notification of the transfer correspondingapplication program 204 d is transmitted to the HMD 10 again, thetransfer display of the application screen can be immediately started.

The termination condition may include, for example, detection of anoperation of terminating the screen transfer middleware 104 b 1 or thetransfer corresponding application program 204 d, or detection of anoperation of turning off a main power of the mobile information terminal80 or the HMD 10.

In FIG. 6 , an example in which the transfer corresponding applicationprogram 204 d of the mobile information terminal 80 is a master whilethe screen transfer middleware 104 b 1 is a slave has been described.Meanwhile, the screen transfer middleware 104 b 1 may be a master andthe transfer corresponding application program 204 d may be a slave, andmoreover, a communication control method in which both of them serve asa master may be employed. That is, after establishing a link byconnection request which is transmitted from the screen transfermiddleware 104 b 1 to the mobile information terminal 80, the activationnotification of the transfer corresponding application program 204 d maybe sent from the mobile information terminal 80 to the HMD 10.

Second Embodiment

A second embodiment differs from the first embodiment in the displaystart condition of the application screen. In the first embodiment, asthe display start condition, a condition as to whether the mobileinformation terminal 80 is present in an image taken by the outsidecamera 3, in other words, whether the mobile information terminal 80 isincluded in the field of view of the user M is employed. Meanwhile, thedisplay start condition is not limited to the one in the firstembodiment. FIG. 12 illustrates a variation of the application screendisplay start condition according to the second embodiment.

The second embodiment uses the following conditions as the applicationscreen display start condition.

Set Condition: Is the application screen set to be automaticallydisplayed on the display 2 of the HMD 10 (step S0911)? In a case ofbeing set to be automatically displayed, the application screen may bedisplayed on the display 2 when the application screen is not includedin the field of view.

Operation Condition: Is it detected that a user operation such as anoperation of a main body button provided on the HMD 10, an operation ofa remote controller, gesture, or the like has been performed (stepS0912)? The application screen may be displayed on the display 2 whenthe operation detection sensor detects the user operation.

Body Motion condition: Is motion of the neck (head) of the user detectedby sensing motion of the HMD 10 based on outputs from the gyro sensor162 and the acceleration sensor 164 of the HMD 10 and each image outputfrom the outside camera 3 and the inside camera 4 to assume that thedetected motion corresponds to the motion of the neck (head) of the user(step S0913)?. Here, the body motion condition is described as thedisplay start condition for performing transition to a displayed stateupon detection of the motion of the neck in a non-displayed state. Onthe other hand, in a case of detecting the motion of the neck in thedisplayed state of the application screen, there is a case where theuser moves the neck to watch the mobile information terminal 80. In sucha case, the motion condition may be used as a condition for performingtransition from the displayed state to the non-displayed state. The HMDcontroller 5 is configured to perform transition of the applicationscreen from the displayed state to the non-displayed state or from thenon-displayed state to the displayed state on the display 2 when angularvelocity included in the output from the gyro sensor 162 or accelerationincluded in the output from the acceleration sensor 164 is equal to orgreater than a predetermined threshold value set to determine that theneck has been moved. In a case of using an image, for example, the HMDcontroller 5 is configured to perform transition of the applicationscreen from the displayed state to the non-displayed state or from thenon-displayed state to the displayed state on the display 2 bydetermining that a place which is watched by the user is changed, thatis, the user moves the neck to see a different place when a differenceamount between the images taken in preceding and following times isequal to or greater than a predetermined threshold value. In FIG. 12 ,it is assumed that the application screen is not displayed beforedetection of the body motion.

Line of Sight Condition: Is it detected that the line of sight has beenturned away from the mobile information terminal 80 (step S0914)? Theimage recognition processing is executed with respect to the image takenby the outside camera 3 to detect on which area of the image the mobileinformation terminal 80 is displayed. Since the outside camera 3, theinside camera 4, and the display 2 are fixed to the wearing body 1,calibration is performed in advance with respect to the relationshipbetween pixel position in each image included in the image taken by theoutside camera 3 on the display 2 and a display position of the display2, so as to generate and store outside camera positioning data.

The line of sight detection sensor 168 is configured to detect the eyeof the user from the image taken by the inside camera 4 so as to detectmotion of the line of sight by tracking change in a position of the eye.Since the relationship between pixel positions in the image taken by theinside camera 4 and a display position of the display 2 is alsoassociated, inside camera positioning data in which they are associatedto each other in advance is generated and stored.

Then, the image taken by the outside camera 3 (mobile informationterminal 80 is imaged therein) and the image taken by the inside camera4 (eye of the user is imaged therein) are compared with the outsidecamera positioning data and the inside camera positioning data,respectively, so as to detect that the line of sight of the user M isturned away from the mobile information terminal 80. It may beconfigured not to display the application screen when the mobileinformation terminal 80 is included in the field of view and when theline of sight is on the terminal display 2, while displaying theapplication screen on the display 2 when the mobile information terminal80 is included in the field of view and when the line of sight is not onthe terminal display 2. In the case above, the application screen may bedisplayed on the display 2 also when the mobile information terminal 80is not included in the field of view.

When the screen transfer middleware 104 b 1 determines that any one ofthe set condition (step S0911), the operation condition (step S0912),the body motion condition (step S0913), and the line of sight condition(step S0914) is satisfied as illustrated in FIG. 12 (step S0911 to stepS0914/either of them is Yes), the value of the application screendisplay flag is set to 1 (step S0916), and the processing is terminated.On the other hand, when it is determined that neither of the displaystart conditions (step S0911 to step S0914) is satisfied (step S0911 tostep S0914/all of them are No), the value of the application screendisplay flag is set to 0 (step S0915), and the processing proceeds to astep for determining satisfaction of the termination condition of theapplication screen display control processing (step S0917). The order inthe determination of satisfaction as to each of the display startconditions is not limited to the order illustrated in FIG. 12 . Inaddition, in FIG. 12 , the processing proceeds to step S0916 when anyone of the conditions is satisfied, meanwhile, it may be configured thatthe processing proceeds to step S0916 when at least one of theconditions is satisfied, in other words, when any one of or a pluralityof combinations of the conditions is/are satisfied.

According to the present embodiment, display or non-display control ofthe application screen can performed by using the display startcondition which is different from the presence or absence of the mobileinformation terminal 80 in the field of view described in the firstembodiment. Accordingly, it is possible to provide an operationenvironment that matches a purpose of use, a situation of use, andpreference of the user M by setting the conditions which is performed bythe user M. In this connection, in the second embodiment, the presenceor absence of the mobile information terminal 80 in the field of viewmay be included as one of the display start conditions.

Third Embodiment

The third embodiment is an embodiment of a variation relating to adisplay position of the application screen. As to which position of thedisplay 2 of the HMD 10 should the application screen be displayed,various modes are conceivable. The following is a list thereof.

(1) Display on Set Position: The application screen may be displayed ona predetermined position such as the right end of the display 2.Furthermore, the HMD controller 5 may be configured to store a positionwhere the application screen was displayed at the termination ofpreceding application screen display control processing (step S09), andwhen the application screen display control processing (step S09) isresumed, display the application screen on the position of the precedingtermination.

(2) Display on Position Corresponding to Type of Application: On whichposition of the display 2 the application screen should be displayed maybe predetermined in accordance with the type of the transfercorresponding application program 204 d. For example, in the case of amap navigation application, the application screen may be displayed atthe right end or the left end of the display 2 which is off the centerof the line of sight in order to secure the field of view in front ofthe eye. On the other hand, in the case of an electronic bookapplication, the application screen may be displayed on the center ofthe display 2 for easy reading. In this way, the display position may bechanged in accordance with the function of the transfer correspondingapplication program 204 d.

(3) Line of Sight Tracking: The line of sight detection sensor 168 maybe configured to continue to detect the line of sight of the user Mbased on the image taken by the inside camera 4 so as to display theapplication screen on a position where the display 2 intersects the lineof sight. For example, in a case where the transfer correspondingapplication program 204 d is a map navigation application, when the userwearing the HMD 10 walks, a map is displayed on the line of sight. Withthis configuration, the road indicated by the navigation can be easilyidentified with the actual road, thereby allowing the user to easilyunderstand the navigation information.

(4) Re-Display Position (after the mobile information terminal 80 insidethe field of view of the HMD 10 moves out therefrom): FIG. 13illustrates a re-display position after framing out. As illustrated inFIG. 13 , in a case where the outside camera 3 generates a plurality offrames along a time series so as to image a motion image, each sideforming an outer edge of each of the frames which constitute the motionimage, each side a, b, c, d of the display 2, and small regions 1, 2, 3,4 of the display 2 are associated with each other in advance. Each ofthe small regions 1, 2, 3, 4 is a region adjacent to each of the sidesa, b, c, d. The screen transfer middleware 104 b 1 may be configured toacquire through which side (outer edge) of a second frame the mobileinformation terminal 80, which was imaged in the first frame, has framedout, and display the application screen in one of the small regions ofthe display 2 which has been associated with the acquired side. Here,the second frame is a frame which is imaged later than the first frame.

For example, as illustrated in FIG. 13 , when the mobile informationterminal 80 frames out from the upper side of the frame imaged by theoutside camera 3, the user M sees that the mobile information terminal80 frames out from the side a of the display 2, and accordingly, theapplication screen is displayed in the small region 1. When the mobileinformation terminal 80 frames out from the bottom side of the frameimaged by the outside camera 3, the user M sees that the mobileinformation terminal 80 frames out from the side c of the display 2, andaccordingly, the application screen is displayed in the small region 3.

In this connection, the screen transfer middleware 104 b 1 may beconfigured to acquire a position on which the mobile informationterminal 80 was displayed immediately before moving out from the display2 so as to display the application screen thereon.

(5) Position Adjustment of Application Screen: The HMD 10 may beprovided with a unit for adjusting a display position after transferringthe application screen. For example, the unit may be configured to, whena swipe operation is performed on the terminal display 281 of the mobileinformation terminal 80, make the application screen of the display 2 ofthe HMD 10 link with the swipe operation so as to change the displayposition thereof on the display 2.

According to the present embodiment, since the display position of theapplication screen can be adjusted in accordance with a purpose of useand preference of the user, it is possible to provide the HMD linkingsystem 100 with higher visibility.

Fourth Embodiment

The fourth embodiment relates to display control of an HMD top screenwhen the HMD 10 is activated after the transfer correspondingapplication program 204 d is activated. FIG. 14 illustrates an exampleof a sequence of the HMD linking system 100 according to the presentembodiment. FIG. 15 illustrates screen transition of the HMD 10.

When the HMD 10 is normally activated, a top screen 1501 of the HMD 10is displayed on the display 2, and then a screen relating to processingof the HMD 10 is displayed.

On the other hand, as illustrated in FIG. 14 , in a case of activatingthe transfer corresponding application program 204 d (step S12) afteractivating the mobile information terminal 80 (step S11) in the HMDlinking system 100, when the HMD 10 is activated (step S15) after makingconnection request (step S13) and transmitting transfer correspondingapplication program start notification (step S14), transition may beperformed from a linkage notification screen 1502 to an applicationscreen displayed screen 1503 or a standby screen 1504 on which theapplication screen is not displayed, without displaying a top screen1501.

That is, at the time of activating the HMD 10 (step S15), the top screen1501 is displayed on the display 2 in the normal activation processing.On the other hand, when the HMD 10 is activated in response to thetransfer corresponding application program activation notification, thelinkage processing between the HMD 10 and the mobile informationterminal 80 is performed thereafter.

Accordingly, after a link is established (step S16), the screen transfermiddleware 104 b 1 is activated (step S17) without displaying the topscreen 1501. The screen transfer middleware 104 b 1 may be configured todisplay the linkage notification screen 1502 in response to linkestablishment, start capturing by the outside camera 3 (step S18), andproceed to the application screen display control processing (step S19).

The present embodiment is for a case where the user M, who wants toperform screen linkage in the HMD 10 after starting use of the transfercorresponding application program 204 d by operating the mobileinformation terminal 80, activates the HMD 10. In this case, the user Mwants to display the application screen on the HMD 10 as quickly aspossible. The present embodiment is configured to display the linkagenotification screen 1502 without displaying the top screen 1501 asdescribed above, and accordingly, the user M does not feel discomfortwhich may be caused by the top screen 1501 that the user M does not wantto watch. As a result, it is possible to reduce irradiation duringwaiting for display of the application screen.

As processing for further reducing the irritation, the linkagenotification screen 1502 may be skipped so as to display the applicationscreen displayed screen 1503. However, in a case where the applicationscreen display start condition is not satisfied, since the applicationscreen displayed screen 1503 is not displayed, the user M cannot confirmwhether linkage has been successfully performed. Accordingly, in thecase above, the screen transfer middleware 104 b 1 may be configured todisplay the application screen displayed screen 1503 immediately afteractivating the HMD 10 when the application screen display startcondition is satisfied, while displaying the linkage notification screen1502 only when the application screen display start condition is notsatisfied. In this case, the screen transfer middleware 104 b 1 may beconfigured not to display the linkage notification screen 1502 in stepS17, but display the linkage notification screen 1502 when theapplication screen is determined not to be displayed on the display 2 inthe application screen display control processing (step S19).

According to the present embodiment, the top screen of the HMD 10 is notdisplayed when it is not necessary in the HMD linking system 100,thereby reducing irritation of the user M and improving convenience.

Each of the embodiments described above is not intended to limit thescope of the present invention. Various modifications may be madewithout departing from the concept of the present invention, and theseembodiments belong to the technical scope of the present invention. Forexample, the first to fourth embodiments may be arbitrarily combined.

REFERENCE SIGNS LIST

-   1: wearing body-   2: display-   3: outside camera-   4: inside camera-   5: HMD controller-   10: HMD-   80: mobile information terminal-   100: HMD linking system

The invention claimed is:
 1. A head-mounted display, comprising: awearing body to be worn on a head of a user; a display provided on thewearing body in front of the user's eyes; a communication moduleconfigured to perform communication connection with a mobile informationterminal; an outside camera provided on a front surface of the wearingbody, which is configured to include a field of view of the user withinan angle of view thereof; an inside camera provided on an inside of thewearing body to face a head of the user; and a controller connected toeach of the display, the communication module, the outside camera andthe inside camera, wherein the controller is configured to: performimage recognition processing of recognizing a subject included in animage taken by the outside camera and sight line detection processing ofdetecting a line of sight of the user based on an image taken by theinside camera; control so as to display an application screen on thedisplay when determining that the subject is not the mobile informationterminal or when determining that the subject is the mobile informationterminal but the mobile information terminal is not on the line of sightof the user, the application screen is a screen which indicates anexecution state of application program executed by the mobileinformation terminal; and control so as to not display the applicationscreen on the display when determining that the subject is the mobileinformation terminal and the mobile information terminal is on the lineof sight of the user.
 2. The head-mounted display according to claim 1,further comprising at least one of a gyro sensor and an accelerationsensor, wherein the controller is further configured to performtransition of the application screen on the display from a displayedstate to a non-displayed state, or the non-displayed state to thedisplayed state when at least one of angular velocity included in anoutput from the gyro sensor and acceleration included in an output fromthe acceleration sensor is equal to or greater than a predeterminedthreshold value.
 3. The head-mounted display according to claim 1,further comprising: an operation unit configured to accept an operationof the user, wherein the controller is further configured to performtransition of the application screen on the display from a displayedstate to a non-displayed state, or the non-displayed state to thedisplayed state when the operation is accepted by the operation unit. 4.The head-mounted display according to claim 1, wherein the inside camerais provided on the inside of the wearing body at a position andorientation on which movement of the eye of the user can be imaged. 5.The head-mounted display according to claim 1, wherein the controller isfurther configured to control so as to display the application screen ona predetermined position of the display.
 6. The head-mounted displayaccording to claim 1, wherein the controller is further configured tocontrol so as to change a position where the application screen isdisplayed in accordance with a type of a function of the applicationprogram.
 7. The head-mounted display according to claim 1, wherein thecontroller is further configured to control so as to display theapplication screen on the display even when the mobile informationterminal is on the line of sight of the user if the application screenis set to be automatically displayed by the user.
 8. The head-mounteddisplay according to claim 1, wherein the display is a transmissivedisplay and the application program is a map navigation application.